Manchester diagrams

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Please reference this figure for the question:

a. Draw a diagram of the signal at point C for the first three characters "NET" encoded as required in problem 3a using NRZ-I

(here is reference from question 3a: The CSU in the communications system is using asynchronous communications with even parity checking.

a. The sequence of bits (Point C) when the characters "NETWORK" are received by the CSU. Assume 7-bit ASCII encoding, 1 start bit (1-bit), 1 stop bit (1-bit) and parity bit..

b. repeat Part A using Manchester encoding

c. repeat Part A again using Differential Manchester

a.

NRZ-I encoading

With NRZ-I a '1' bit is represented by 0 volts or +V volts depending on the previous level. If the previous voltage was 0 volts then the '1' bit will be represented by +V volts, however if the previous voltage was +V volts then the '1' bit will be represented by 0 volts. A '0' bit is represented by whatever voltage level was used previously. This means that only a '1' bit can 'invert' the voltage, a '0' bit has no effect on the voltage, it remains the same as the previous bit whatever that voltage was.

For "N" the signal will be:

For "E" the signal will be:

For "T" the signal will be:

Manchester Encoding:
Manchester encoding is a synchronous clock encoding technique used by the physical layer to encode the clock and data of a synchronous bit stream. In this technique, the actual binary data to be transmitted over the cable are not sent as a sequence of logic 1's and 0's (known technically as Non Return ...